THE UNLOST RIVERS OF LONDON Pymmes Brook Monken Hadley → Arnos Grove → Tottenham Hale (4½ miles)
[Pymmes Brook → Lea → Thames]
Pymmes Brook is one of North London's longer rivers, though not especially well known. It flows mostly through Barnet and Enfield, for the most part above ground, then somewhere around Edmonton heads underground before emerging as a tamed brutalist channel. A ten mile waymarked route follows the brook downstream - the Pymmes Brook Trail - the first half quite pleasant and the second part rather less so. Today I'll write about the half of the walk you might actually enjoy. Should you fancy following along, Barnet Council alas no longer publish their free trail leaflet, so walkers have to make do with a slowly decaying set of signs and some onlinemaps which aren't 100% accurate. I got by well enough.
The source of Pymmes Brook is at Monken Hadley, a hilltop village on the very northern edge of London. Officially this first tributary is called the Monken Mead Brook, a minor streamlet which rises on private land and then curves east through the commuter suburb of Hadley Wood. The Pymmes Brook Trail ignores all of this, and rightly so, kicking off instead some distance away at Cockfosters station. A set of signs points the way from the bus stop outside to the edge of Monken Hadley Common, following precisely the same route as London Loop section 16 if you've ever walked that. The last quarter of a mile down a wooded track to the valley floor is splendid, and possibly the only part of the entire walk that might muddy your trainers in winter. It's a fine start.
The trail proper kicks off at a narrow footbridge just below Beech Hill Lake. You won't immediately spot the lake unless you've got a map, but if you take a few steps upstream you'll reach the dam of a long blue pool tapering off into the distance, its surface liberally dotted with lilies and waterfowl. I stepped up, only to be eyed suspiciously by the anglers who've adopted this place as their own, so slipped uncomfortably away. Instead I started my long walk south along the river, passing a couple of school entrances (and several butterflies) before entering a housing estate where undeveloped countryside abruptly terminated.
The avenues of outer Cockfosters are pleasant enough, and well-served by meandering bus. Here the Pymmes Brook Trail signals its intent not to strictly follow its eponymous waterway by diverting into a neighbouring recreation ground, ostensibly because the view is better. And indeed it is, if you like sunbathing space, gasholders and a fenced-off water fountain. Victoria Rec is also the location of the East Barnet Valley Bowls Club, whose somewhat retro admission procedure requires you to drop your contact details into their letterbox and await a phone call.
Returning to the streets, the brook runs out of sight behind Crescent Road, where the contours provide adequate opportunity for a hillstart, and a couple of houses have such steeply-sloping gardens that their garage is at first floor level. Ahead are Brookhill and Cat Hill, similarly inclined, and the attractive heart of East Barnet Village. This slightly old-fashioned retail parade clusters around the war memorial and some dazzlingly pristine flowerbeds, and boasts an actual gunshop called Gunshop for all your suburban rifle and revolver needs.
It should be obvious where to go next - one of the adjacent roads is called Brookside. A run of semi-detached houses faces a large lawn tumbling down towards the re-emergent river. Looking across it's clear that the brook has carved a significant notch in the local landscape, however humble its waters now seem. This becomes even clearer ahead at Oak Hill Park, the largest recreational space along the route, and much loved in summer by the local populace, their offspring and their dogs. Nowhere else does Pymmes Brook look more like a proper river, ambling in a shallow channel beneath dangling willows, the contrails of passing jets reflecting in its rippled surface. Oak Hill's a good place for a rest, or a diversion up the woodland trails, or an ice cream from the pitch and putt.
Departing the park, the brook returns to residential streets. Specifically it forms a dividing line between two unimaginatively-named streets called West Walk and East Walk, each with semis on one side and a broad communal lawn stretching down to the river on the other. You'll see this kind of landscaping on several other London estates, but here it's particularly nicely done, not least thanks to the green-painted very-mid-20th-century design of the ironwork on several of the low bridges. Officially this grassy gap, named Everleigh Walk, is to prevent flooding affecting the adjacent properties, although the gradient suggests the west side is in considerably more danger than the east should this ever happen.
Take note of the bleached-out waymarking signs on Osidge Lane and head to the left-hand bank of the river to continue. This is to follow the Waterfall Walk, a mile of uninterrupted weaving tarmac which, though very pleasant, could perhaps be challenged under the Trade Descriptions Act. I neither heard nor saw any waterfalls, nor even anything vaguely weir-like, although the river itself was well shielded throughout, breaking out only occasionally through thick seasonal undergrowth. Much more obvious was the tinder-dry meadow at the northern end, gradually narrowing as the back garden fences of Osidge residences creep closer and a tennis club squeezes in.
And then come the arches, 34 lofty brick arches which are first seen spanning Waterfall Road. Here they enter Arnos Park, which might be a clue to the railway floating overhead, and the tube station just around the corner. That's Arnos Grove, and the occasional rattles overhead belong to Piccadilly line trains, indeed you might well have passed this way on your journey to the start of the Trail. This is the Arnos Park Viaduct, opened in 1933 when the Underground extended north, and one of the architectural wonders of the London borough of Enfield. It looks quite impressive from the side, but the best thing is that you can walk underneath and step through a chain of umpteen smaller arches.
After half a dozen or so arches on the western side the Pymmes Brook wiggles through, undertaking two right-angled turns to pass smoothly with minimum erosion on the brickwork. The trail doesn't cross back over but you should, and take your camera, to grab a few specialgeometricshots as the sequence of gradually diminishing spaces curves off into the shadows.
Head up to the shallow end and you might be tempted to join the Arnos Bowling Club, who offer "free coaching and tea" if the banner facing the viaduct is to be believed. Or take a look around the extensive parkland before deciding where best to head next. The Underground's most magnificentstation building is but a short walk away, and there'd be no disgrace in bailing here, because the best miles of the Pymmes Brook Trail are behind us. A great all-seasons stroll, I'd say, as many of the outward-looking residents of outer north London know well.